The present invention relates to a frame apparatus of the kind which is constructed to be mounted on the trunk of a tree for use by arborists in handling loads involved in arbor rigging procedures.
The present invention relates particularly to a frame apparatus of this kind which conforms to the curvature of the trunk of the tree and engages the trunk at three triangularly disposed locations.
The triangular, three point engagement of the frame apparatus with the trunk provides a very stable mounting of the frame apparatus on the trunk.
The U.S. Pat. No. 4,239,188 issued Dec. 16, 1980 to Hobbs and entitled "Tree Handling Device" and the U.S. Pat. No. 4,314,693 issued Feb. 9, 1982 to Hobbs and entitled "Device for Arborist Contractors" disclose tree handling devices used by arborists for handling heavy tree limbs cut from a tree during arbor rigging procedures. Each of these patents is incorporated by reference in this application.
The device shown in U.S. Pat. No. 4,239,188 requires that a notch be cut across a portion of the circumference of the tree or that pins be inserted into the tree for secure engagement of the tree handling device with the tree.
The device shown in U.S. Pat. No. 4,314,693 does not require prior notching or slashing of the tree trunk, but the frame of the U.S. Pat. No. 4,314,693 patent device engages the trunk with just two horizontally extending flange members, an upper flange member and a lower flange member. Both flange members have straight edge surfaces without any curvature. The straight edges of these two flange surfaces engage the trunk in small strips of contact. The entire frame is therefore mounted on the trunk with just a small upper strip of contact and a small lower strip of contact.